Where are you trying to sign in, Joey - in Lightroom Desktop or in the mobile app on your mobile device? If in Desktop, what shows in the Lightroom mobile tab in Lightroom>Preferences? Does that show you signed in?
If you're signed in, try checking the sync box to the left of a collection. Is there a message above the identity plate in the top left that the photos are syncing?
For once you get signed in, here's a video tutorial on how to get started with Lightroom mobile.
I´m trying to sign into the Desktop version. Using the 'Sync with Lightroom Mobile - Sign In'.
But nothing happens when I use that option.
In preferences > mobile it say's I'm not connected with Mobile.
Signing into Lightroom Mobile on my phone is not a problem. But I need to sync between the two.
Fixed by Adobe Customer Service.
Im having exactly the same issue. how did you fix this?
Joey, I don't know if customer service fixed everything. But the version number that you cited indicates that you are using the initial installation of Lightroom CC 2015. There have been 12 updates. You should check for updates because you don't have the latest update, at least based on the version number that you listed.